Printing cylinder bearer



Nav. 7, 1944. w E .HUCK 2,362,069

PRINTING CYLINDER BEARER Filed June l, 1942 4 Sheets-Sheet 1 20 P l n 3.5

377` avag 37 3 Siwa/WTO@ 30* `31 f l Milam i? 17ml LM Stmmen,

NOY. 7, 1944. w, F HUCK 2,362,069

PRINTING CYLINDER BEARER Filed June 1, 1942 4 sheets-sheet 2 rfi/W m I ,Um

WZZz'amE/Yaffi Nov. 7, 1944. w, F, HUK 2,362,069

\ PRINTING CYLINDER BEARER Filed June 1, 1942 4 Sheets-Sheet 3 ,fg/ai Nov. 7, 1944.

w. F. Hu 2,362,069

PRINTING CYLINDE Filed June '1,

12 @www 4 Sheets-Sheet 4 Patented Nov. 7,1944

PRINTING CYLINDER BEARER William F. Huck, Richmond Hill, N. Y., assigner to R. Hoe & Co., Inc.,

porationrof New York Application June 1, 1942, seria1N0'445s4 11 claims. iol. 10i- 216) This invention relates to bearers for cooperating rotary cylinders, and more particularly to bearers for application to coacting printing cylinders.

In the operation of cooperating printing cylinders, such as employed in newspaper, magazine, lithographie, and other printing machines, printving plates or forms of predetermined thickness are secured to the plate or form cylinder of each printing couple, and suitable impression members, such as blankets or the like, are secured to the impression cylinder of the couple in such relation that a web or sheet is printed/between the plates and the impression blanket.

In order to secure the best results, the impression blanket should press the paper against the image producing faces of. the plates or forms with considerable pressure, and this pressure should be maintained at a constant value throughout each rotation of the printing cylinder.

In large printing machines which print on wide webs, the pressure required for printing is suficient to produce a small amount of deflection oi the cylinders, and if the bodies of the cylinders are of the same diameter throughout their length, this would result in causing the printing plates that are near the center of the plate cylinder to print lighter than the plates at either end. This condition is commonly corrected however, by

packing under the blanket on the impression cylinder, or under the backs of the center printing plates with paper, so as to-produce equal pressure on al1 of the plates. This, of course, further increases the cylinder deiiection. On some machines, the bodies oi the cylinders are made with a slight taper toward each end, the diameter at the center being sufficiently larger than the diameter at the ends, so that eXtra packing to correct for deiiection is unnecessary.

In order to constantly maintain proper print-` ing relationship of the cylinders, bearers are provided at the, extremities of each cylinder. These bearers are usually cylindrical rings that are shrunk or otherwise secured on the ends of the cooperating plate and impression. cylinders, and so positioned that their peripheries` are in rolling Contact. The vbearers may however, be formed integral with the` cylinder or shaft.

An important function of the bearers is to prevent the printing cylinders from moving bodily toward each other at certain times during each revolution, when the spaces between the adjoining straight edgesl of the printing plates are passing `the bite of the cylinders. At such times the pressure on the cylinder bearings due to impres- New York, N. Y., a corsion pressure is entirely absent, and even a very small looseness in -any of these bearings would permit an objectionable motion of thecylinders, if they were not provided with bearers.v

To maintain proper impression pressure between the impression cylinder and cooperating platey or form cylinder, the coacting bearers are pressed towards each other under a stress which is sulicient t0 slightly distort or iiatten the contact yportions of the bearers, and the relatively long printing cylinders are bent so that their normally straight axes of rotation are deeoted and deiine arcs that are bowed in directions away from the contacting portions of the cylinders. Although this deflection is very slight, it is sufficient to cause the outer edges of the peripheries of cylindrical bearers to be placed under greater stress than any other portion. This excessive stress tends to overload the metal, so that in time it will fatigue and crack where thus stressed, and after continued use, these cracks will extend sufficiently to cause a break. In relatively short`V printing cylinders, the deection may not be suincient to produce appreciably greater stress at the outer edges of the bearers than at their inner edges, but even under this ideal condition, the bearers are pressed together under relatively heavy stress, which stress is suiicient to flatten or deform the bearers at their contacting spots, and the strain or deformation produced by this stress is greatest at the edges of the bearers, so that cracks or ruptures usually start at these places, and in time, spread suiiiciently to cause failure of the bearers.

It has been found that with cylinder bearers rolling in contact with each other and under relatively heavy stress, if the axes of the cylinders are parallel the resulting stress is greatest at the edges of each of the bearers, and if the impression pressure is sufficient to cause the cylinders to be deflected away from each other, then the greatest stress is imposed at the outer edge of each of the bearers, and in either case the additional stress at the edges of the bearers tends to fatigue the material sufficiently to startcracks or ruptures at the highly stressed edges of the bearers. It has also been found that if the stresses in cooperating bearer rings are reduced or eliminated at the edges of the bearers, then the life of the bearers is greatly prolonged.

It is, therefore, an object of this invention to provide bearers for coacting printing cylinders, the bearers being located for rolling contact with l each other, and being so formed as to reduce or eliminate stresses and strains at their edge portions.

Another object of this invention is to provide bearers for coacting printing cylinders or the like, which bearers engage each other in rolling contact under relatively heavy stress, the conguration of each bearer being such that the stress existent at either of its edges is of much less magnitude during its operation than, the stress existent elsewhere on the bearer.

A specific object of this invention is to provide coacting bearers for rolling engagement at the ends of coacting rotary cylinders, each bearer having a peripheral face which is greater in diameter at its intermediate portion than at its edges.

A more specic object of this invention is to provide coacting bearers for rolling engagement at the ends of coacting printing cylinders, each bearer having a peripheral face which is greater in diameter at its intermediate portion than at the portions adjacent its edges and its diameter being gradually reduced as the edges of the bearer are approached.

It is also an object of this invention to provide a cylinder bearerv of generally improved construction, whereby the device will be simple, durable, and inexpensive in construction, as well as convenient, practical, serviceable and eicient in its use.

With the foregoing and other objects inview, which will appear as the description proceeds, the invention resides in the combination and arrangement of parts, and in the details of construction hereinafter described and claimed, it being understood that various changes in form, proportion, and minor details of construction may be made withinl the scope of the claims Without departing from the spirit or sacricing any advantages ofthe invention.

For a complete disclosure of the invention, a detailed description of it is given in connection with the accompanying drawings forming a part of the specication, wherein:

Figure l is an elevation of a conventional printing couple, showing the invention applied thereto, the frames of the machine being shown in section;

Figure 2 is a fragmental elevation of a pair of improved cooperating bearers depicted in their normal condition, one of the bearers being broken away to show a portion in section;

Figure 3 is a side elevation of an improved bearer, the supporting cylinder being shown in section;

Figure 4 is a fragmental elevation of the bearers depicted in Figure 2, but on which bearers sunicient compression stress is exerted to deform the bearers along their contact portions;

Figure 5 is a fragmental diagrammatic view depicting a pair of cooperating conventional bearers on which suflicient compression stress is exerted to deform the bearers along their contacting portions, the deformation being exaggerated;

Figure `6 is a view of the improved type of bearers disclosed in Figure 2, depicting in exaggeration the effect on the bearers of compression stress, similar to that depicted in Figure 5;

Figure 'l is a ragmental diagrammatic view of conventional bearers, similar to Figure 5, but

showing the bearers in axially offset relation and depicting in exaggeration the effect of the compression stress when the bearers are so disposed;

Figure 8 is a view of the improved type bearers, showing the effect of the compression stresses i when these bearers are disposed in the same axially oiset relation as those shown in Figure 7;

Figure 9 is a fragmental diagrammatic view of conventional bearers, similar to Figure 5, but depicting in exaggeration the effect of the compression stress on the cooperating bearers when the axes of the bearers are not in parallelism with the contact line or plane of the bearers;

Figure 10 is a view, depicting the eiect ol the compression stress on the improved type of bearers disclosed in Figure 2, under the conditions existing in Figure 9;

Figure 11 is a fragmental diagrammatic view similar to Figure 9, but depicting the cooperating conventional bearers in axially offset relation;

Figure l2 is a view, depicting the effect of the compressive stresses on the improved type ol bearers disclosed in Figure 2 when such bearers are disposed, similarly to those in Figure 11, in axially oiTset relation;

Figure 13 is an elevation, parts appearing in section, depicting another form of improved cylinder bearer, the bearer being depicted as secured to a cylinder;

Figure 14 is a fragmental diagrammatic view depicting the type of bearers disclosed in Figure 13 in cooperating relation under compressive stress, the deformation of the bearers being exaggerated;

Figure 15 is a view similar to Figure 14, but depicting the bearers in such relationship that their axes are not parallel with their plane of contact;

Figure 16 is an elevational view of the type of bearer disclosed in Figure 13, depicting in exaggeration the area of deformation of these bearers when operating under compressive stress, the view being seen on the plane indicated by line lli- I6 in Figure 14;y

Figure 17 is a fragmental elevation, partly in section, of a modified bearer arrangement;

Figure 18 is a view depicting a bearer similar t0 that shown in Figure 2 but adapted more particularly to relatively slender cylinders that are more likely to be always bowed during normal operation of the machine;

Figure 19 is a view depicting a bearer similar to thatshown in Figure 2, illustrated in ruiming engagement with a cooperating bearer having a periphery that is cylindrical throughout its width;

Figure 20 is a view of a bearer similar to that shown in Figure 13,'illustrated in running engagement with a bearer having a periphery that is cylindrical throughout its width; and

Figure 21 shows a fragmental sectional View of two cooperating cylinders with bearers formed integral therewith, one of the bearer surfaces being similar to that of Figure 2 and the other bearer surface being cylindrical.

Referring tothe drawings, in which similar reference characters designate corresponding parts, 26 indicates a plate or form cylinder which cooperates or coacts with an impression cylinder 2|. The cylinder indicated is of the type employed in magazine presses, although the invention is applicable to newspaper presses, offset presses and other printing machines which employ printing couples having cooperable cylinders. Each cylinder is rotatably mounted in bearings 22 which are supported in frame members 23 of the printing machine. Any desired type of bearing may be employed, but preference means for effecting its adjustment radially with respect to the impression cylinder 2|. Any desired form of radialv adjusting mechanism may be employed, though preference is given to the type shown in United States Lamatsch Patent No. 1,824,436, As herein shown, the bearings 22 of the plate cylinder 20, are mounted in eccentric sleeves 25 Which are rotatable relative to the frame members 23, and rotary movement of the eccentric sleeves 25 causes the plate cylinder to be adjustably moved in radial relation to the impression cylinder 2|, in conformity With thel usual practice in structures of this character.

As herein shown, the plate cylinder 20 is provided with eight printing plates P disposed in two' axially aligned rows, which is a disposition that may be employed in magazine p-resses, although the plates may be located on the cylinder in staggered relation for newspaper printing, or in any preferred relationship forprinting of any character. The impression cylinder 2| is provided with the conventional impression blanket B, and this blanket forces the paper against the printing faces of the plates P and provides the requisite printing impression between the cooperating printing cylinders. The plates P do not extend sufficiently around the cylinder 20 to cause their straight edges to abut, consequently gaps G are left between adjacent plates P. While the printing faces of the plates P are in engagement with the blanket B, the cylinders may rotate with their axes in constant radially spaced relation, but when the gaps G are opposite the blanket B, the impression pressure is momentarily released and the faces of the cylinders tend to approach each other until the opposite side of the gaps is reached,and then the cylinders again establish the impression pressure. From the foregoing, it is seen that if no provision is made to hold the cylinders in uniform radially spaced relation, these cylinders tend tc approach each other when the gaps G of the printing plates P are passing the bite or line of engagement of the cylinders.l This objectionable relative radial movement of the printing cylinders of a printing couple is usually prevented by placing a conventional cylindrical bearer ring 2,1, of the type shown in Figures 5, 7, 9 and 1l, on a reduced portion 23 formed at each terminal of each cylinder, and the bearers 21 are preferably located so that the periphery of each bearer on one cylinder is in yrolling or rotating engagement with the periphery of a bearer on the cooperating cylinder. These conventional bearers, as stated, are in the form`of cylindrical rings, the outer cylindrical faces of which have the same diameter throughout and terminate in square corners at each edge.

Deflection of the cylinders that is caused by the impression pressure is indicated in greatly exaggerated degree, by the dotted lines 32 and 33 in Figure l. Under the lighter printing impression pressures, the cylinder may remain substantially parallel, but the cooperating bearers are nevertheless subjected to` stress sumcient to deform their contact portions, as will be more fully explained. hereinafter. This deformation is greatest at thel edges of each bearer, withthe` result that metal fatigue is manifested in the form` of cracks or ruptures of the material at these places, and in time they spread, resulting in a complete failure of the bearer. This bearer fatigue is accentuated if sufficient impression pressure is imposed on the cylinders to cause excessive cylinder deflection. As shown in Figure 1:, when `the cylinders are deected, the bearers tend to tip outwardly so that their outer edges are subjected to stress of greater magnitude than their inner edges, thus causing cracksor ruptures to start at the outer edges of the cooperating bearers.

The breakage of cylinder. bearers has become a serious problem, and applicant has solved this problem by providing bearers in which the conventional outer cylindrical; faces of the bearers are altered; to completely change the distributionr of the stresses built upv in the engaged portionsL of the bearers duringl their normal operation.

Applicants improved bearer may. bein the form of a ring which is secured to the cylinder, an acceptable form being disclosed in Figures l, 2, 3., 4, 6, 8, l0 and l2. lIn this form, the inner face of the bearer 35 is formed by a cylindrical bore 3A, the terms cylindrical and cylinder being used herein to denote-a circular cylindrical shape. The borev of the bearer 35 is fitted tothe reduced portion 28 of the cylinder, and the ilat annular surfaces or end 'Walls 30- and 3| are preferably made perpendicular to the inner face 0r bore 34.-

The` peripheral face of the bearer 35 comprisesv a cylindrical. center or intermediate portion 3S (best seen inFigure 2), andk preferably tapered and rounded portions 3l and 38 which extend from each side of the center portion to the sides or edges of the bearer. In section, the tapered portions 37 are curved transversely of the bearer, the curve preferably being an arc, to which the line denoting the face 35 in Figure 2 is tangent.

i. The tapered portions 3l' thus smoothly merge into the cylindrical portion 35, and the smaller diameter side of eachtapered portion 37 meets and merges into a portion 38 Which extends to the side or edge of the bearer and forms a rounded corner. i,

By this arrangement, when the bearers 35 are running in cooperable rel-ation under heavy im pressionv stress, the cylindrical intermediate portiony 36 of each bearer face will be pressed inwardly so that a part of each tapering portion 3l is flattened and blends into configuration with the cylindrical portion 36, but the rounded corner portions 3S do not flatten, consequently leaving a. slight space at the edges of the cooperating bearers 35 where they do not make contact. Although rounded corners 38 are disclosed in this fom of the improved bearer, it is to be understood that these corners may be beveled or otherwise shaped to reduce the effective diameter of the bearer at these locations. This flattened 'condition is best shown in exaggeration in Figures 4 and 6; and this theoretical relationship is found when the impression pressures are relatively heavy, butv not suflcient to appreciably deflect the axes of' the cylinders 2G and 2|. In this relationship, the imposed impression stresses cause the contacting portions di! of the conventional bearers-` 2l.- to be deformed, so* thatthe width of 'their faces is increased, as indicated in exaggeration at 4| in Figure 5. The magnitude of the eiective` In diagramamtic Figure 6, there is depicted the stresses existent when the improved bearers 35 are employed instead of the conventional bearers 2l under the same conditions as shown in Figure 5. The tapered faces 31 of the improved bearers 35 flatten, but the rounded corners 38 prevent the edges of the bearers 35 from contacting. It will be observed that the magnitude of the stress imposed on most oi the bearer area has been very slightly increased, as indicated by the lines 42a, but the stresses at the edges drop` to zero, so that at the rounded corners 33, the bearers 35 are free of all stresses. It is manifest, therefore, that no cracks or ruptures can start at these places, as the result of even excessive pressure.

Experiments and experience have proven that cracks or ruptures seldom occur in the intermediate portion of bearers formed or" satisfactory material, consequently applicants invention provides an improved bearer which so distributes the stresses due to heavy printing impression, that bearer failure is prevented.

In Figure 7, an arrangement is depicted in which the conventional square edge bearers 2l are running in the relationship shown in Figure 5, but in which one bearer has been moved axially relative to the other, which relationship frequently results when a cylinder adjustment is made in order to effect accurate registration. In this relationship, the composite stresses are indicated by the lines 42h, and it will be observed that although different from Figure 5, the maximum stresses under this condition also, are present at the edges of the engaged portion of each bearer.

In Figure 8, a similar disposition of the bearers is indicated, but the improved bearers 35 have been substituted for the conventional bearers 21. The resulting stresses have been indicated by lines 42C, and it will be observed that while the amplitude of the stresses on most of the bearer area is somewhat increased over the conditions depicted in Figure 7, the stresses at the edges drop to zero, and thereby prevent cracks or ruptures from starting at these places.

In diagrammatic Figure 9, there is depicted an arrangement in which the conventional bearers 2l are running under impression stresses in the approximate relationship depicted in Figure 5, but in which the bearers have been slightly tipped from thevertical by the deection of the printing cylinders which as stated, is quite a usual condition. The outer surfaces of the bearers will then ybe ilattened to a greater extent at their outside edges, which are farther from the center of the cylinder, and flattened at a lesser extent at their inside edges, which are nearer the center of the cylinder. The impression stresses are indicated by the lines 42d, and it will be observed that the stresses are increased at the edges of the bearers, with the greatest stresses occurring at the outside side or right hand edge of thek engaged bearers, assuming, of course, that these bearers are positioned on the right hand end of cooperating cylinders. The stresses resulting at the intermediate portions of the bearers have their magnitude gradually increased as they approach the right hand edge of the bearer, as indicated.

A similar condition is depicted in Figure 10, but here the improved bearers 35 are substituted for the conventional bearers 2l, and in this relationship the stresses are indicated by the lines 42e. The stresses at the intermediate portions of the bearers are slightly greater than those indicated in Figure 9, but it will be seen that the magnitude of the stresses at the edges drop to zero, so that no stress is p-resent at the rounded edges of the bearers even though the cylinders are deiiected, thus preventing ruptures from starting at these locations.

Figure l1 depicts a relationship caused by cylinder deflection, as in Figure 9, but in which one bearer is moved axially relative to the other as in Figure 7, to meet accurate register requirements. In this relationship, the magnitude of the stresses is indicated by the lines l2f, and it will be observed that the stresses of greatest magnitude are at the edges of the engaged portions of these bearers with the greatest stresses occurring at the right hand side or outside edge of the bearers, somewhat similar to the arrangement depicted in Figure 9.

Figure l2 depicts a condition similar to that shown in Figure ll, but in which the improved bearers 35 have been substituted for the conventional oearers 2l'. In this relationship, the magnitude oi the stresses is indicated by the vertical lines Mg, and it will be seen that the magnitude of the stresses at the intermediate portions oi the bearers has been slightly increased, but the stresses at the edges drop to zero, and th'us prevent breakage starting at these places, even though the cylinders are deflected and the bearers out of alignment.

In revie ing the foregoing, it will be seen that applicant by providing the improved bearer with a cylindrical peripheral face and with rounded edges, as herein disclosed, has produced a bearer which may run under heavy stresses in cooperative engagement with a similar bearer in either perfect cr moderately imperfect relationship, and in which the stresses due to impression pressure are so distributed that they are reduced to Zero as they approach the edges of the engaged portions of the cooperating bearers.

It will be observed from Figures 9 and l1 that the stresses at the inside edges of the bearers are not great, and hence the inside corners may be left square without probability of having excessive stresses develop at these places. However, it is preferred to shape the bearers so that their contact, close to the inside edges as Well as to the outside edges is prevented.

Another form of the improved cylinder bearer is shown in Figures 13 to i6, and indicated by the numeral 5B. This form is similar to the form depicted in Figure 2, but instead of having a cylindrical central peripheral portionA the greater part of the peripheral face 5i of the bearer 50 is crowned or curved transversely of the bearer, so that the peripheral face tapers from a maximum diameter at 52 to smaller diameters near the edges where it meets and merges with the rounded corners 33.

This bearer 55, as shown in Figure 13, has its inner face formed by a tapered bore 34a instead of the cylindrical bore shown in connection with the bearer 35, and a bearer 50 is applied at each shrinking it in place. `It will be understood, how

ever, that the type of bearer shown in'Figure 13,

may be formed `with a cylindrical bore, the same as that shown in Figure 2. Referring further to Figure 13, the crowned face l is preferably an arc having a relatively great radius R about a center A, which is located outside the connes of the bearer.

Referring to Figure 14, there is depicted a cori-- ditionin which cooperating bearers I56 are running under relatively heavy stresses, and with lthe bearers in radial alignment as with the cylinder axes parallel. In this relationship, the magnitude of the composite impression stresses is indicated 'by lines 42h, and it will be observed that .the stresses of greatest magnitude are `centered over the portion of the'bearers 56, that are normally of maximum diameter, and these stresses are reduced to Zero before theedges Yof the bearer are reached. In this arrangement, `the maximum stresses are somewhat higher than the maximum I stresses found in 4the form of bearer depicted in Figure 2, .but the arrangement is preferable in.

other respects.

As the peripheral face lof these bearers 50 are crowned, when they are deformed or flattened at their contact portions by the impression stresses, the area of this deformation is of elliptical outline, as indicated in exaggeration in Figure 16.

Figure 1:5 is similar to Figure 14, but depicts the bearers 5] as operating under conditions where the axes of the cylinders 'have been ydelected so that the bearers are disposed at an angle relative vto each other, the angle, however,

being greatly exaggerated. In this figure, the magnitude of the impression stress is indicated by lines 421, and it will be observed that the stresses are `greatest'over areas similar in size and shape vto those in Figure 14, but the areas are now located nearerthe inside edges of lthebearers. Although the point of imposition of the greatest stresses has been shifted 'to a point much nearer one-edge of each ofthe cooperating vbearers, it will vbe seen that the stresses show the same characteristics as in Figure 14 and still drop to zero at the outer rounded corners 38, thus preventing a breakage or rupture occurring at this point. When bearers of the form shown in Figure 13 are operated under the conditions as represented in Figure 12, the area of contact and consequently the stresses will be the same as in Figure 15.

It will be understood that with the form of bearer shown in Figure 2, the stress curves may vary from that shown in Figure 6 with no cylinder deflection, to that shown in Figure 12 with maximum deflection and misalignment, but with the form of bearer shown in Figure 13, the stresses are the same under all conditions.

As hereinbefore stated, the improved bearer may be formed as an integral part of the supporting cylinder, and such arrangement is depicted in Figure 17. In this arrangement, the cylinder 20a has a bearer 50a formed integral therewith at each end, and the outer peripheral faces of the bearers are crowned in conformity with the bearer structure depicted in Figure 13. Inthe form here illustrated, the bearer 50a is provided with ya crowned peripheral `face 5l a, and the'edges of -the peripheral :face 51a are defined by beveled or chamfered surfaces which form frusto-'conical `faces 38a. If preferred, however, the rounded corners 38, best depicted in VFigure 13, may be 'substituted for the frusto-conical faces 38a. I

Inasmuch as this .form of bearer is-provided with a crowned :peripheral face 151m, `fits operatingcharacteristics are similar Ito those of lthelstructure depicted tin Figures 13 Ito 16, .hereinbefo-re described.

The bearer 55 adepicted 1in Figure 118 is provided with `asrounded corner 3`8c at its inside edge, the arc yhaving a vrela-tivelyshOrtradiuS. A cylindrical surface 36e 'extends throughout the greater portion of its width,.and ri'he'peripheral area `adjacent to its outer .edge is formed with tapered and rounded portions 31o and 38e, as in theiorm shown in `Figure 2. On printingcylnders having .a diameter that is small relative to their length, and in consequence that are always bowed outwardly -to some extent, there `is no necessity for providing fa curved `face area on the inside edge of the bearers, and `bearers of the type shown in Figure 18 are preferable, as the pressure may be distributed over a greater area than with bearers as shown in Figure 2. f

Figure 19 depicts a .bearer V58, the Aperipheral 'surface of which is similar to that shown'in `Figure 2. It is arranged-in running engagement with a cylindrical bearer 59only a partof lwhich is shown. It will be seen from this figure, that if preferred, a bearer r58 made Ain .accordance with the invention and having tapered and curved peripheral areas 31d .and 38d respectively, maybe operated against a bearer A59, the .surface v59d of which is cylindrical throughout its width, and it will be `understoodrthat there will `be no excessive pressure 4imposed on eitherof the Yedges of the bearer, the result of the imposition `of pressure on bearers thus arranged being substantially the same as illustrated .in Figures 6, 8, 10 and `12, under corresponding conditions.

In Figure 20, .a'bearer 6| .having acrowned peripheral vface .5Ie with rounded corners `38e and of .the type shown in -Figure 13, is shown in connection with a bearer 62 having a face 62e that is cylindrical .throughout fits width, .and it will lbe understood that when pressure is imposed on bearers `thus arranged, Ythat the result will be substantially-the same as vis shown in IFigures .14, 15 and 16.

Figure .21 shows in section, av small portion of two cooperating printing cylinders `26) and Zlf with bearers formed integral with the cylinders, and being similar in this respect to Figure 17; but in this iigure, the engaging surfaces of the cylinders 201 and 2|]c are formed the same as the engaging surfaces of the bearers 58 and 59 in Figure 19, and the eiiect on their peripheries of pressure incident to adjusting the cylinder bearings for printing, would be the same asin Figures 6, 8, 10 and 12.

From the foregoing it will be seen that applicant has produced a bearer that will insure relatively long operating life under the most severe printing impression stresses, and Will also save time and expense in the maintenance of printing machinery by avoiding the serious delays and costs incident to bearer failures, l

It will be understood that the invention herein disclosed may be embodied in other speciiic forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being had to the claims rather than to the foregoing description to indicate the scope of the invention.

What I claim is:

1. The combination with coacting printing cylinders, of coacting bearers supported by the cylinders in rolling engagement, each bearer having a cylindrical bore forming an inner surface to engage its supporting cylinder, annular surfaces at each end of the bore and a peripheral face in concentric relation with the bore, the thickness of the bearer as dened by the radial distance between the bore and the peripheral face being greatest at an axially intermediate portion and this thickness gradually reduced at each side of the point of greatest thickness.

2. A printing cylinder bearer having a cylindrical bore, a transversely curved peripheral face surrounding the bore in concentric spaced relation and defining the thickness of the bearer, and annular end walls disposed perpendicular to the bore and dening the edges of the bearer, the thickness of the bearer at a point intermediate its end walls being greater than the thickness of the bearer at the end walls.

3. A printing cylinder bearer having a peripheral face, the diametrical dimensions of the bearerl being dened by a iirst peripheral face portio-n having the maximum diameter of the bearer, and an adjoining tapering face portion at each side of the rst face portion and curved to merge with the first face portion, and a rounded corner at each edge of the face.

. 4. A cylinder bearer having a transversely curved peripheral face which denes the diametrical dimensions of the bearer and which is of such configuration that the bearer is greater in diameter at an intermediate portion than at its terminals. f

5. A printing cylinder bearer having a maximum diameter at an area midway transversely of its face, the face being curved transversely of the bearer and tapering to a smaller diameter adjacent its outside edge, whereby deflection of the cylinder carrying the bearer will prevent a concentration of pressure close to its outer edge when it is pressed against a bearer face on a coacting printing cylinder.

6. A printing cylinder bearer having its maximum diametrical dimensions defined by a peripheral face portion cylindrical in form, and with an adjoining transversely curved smaller diameter portion at the side of the cylindrical portion,

the said smaller diameter portion having a face forming a rounded corner at an edge of the bearer and curved to merge with the cylindrical portion.

7. A cylinder bearer having its diametrical dimensions defined by a peripheral face having a cylindrical center portion and a tapered portion at each side of the cylindrical portion and curved to merge therewith, the cylindrical face being of maximum diameter and the tapered portions being rounded at the edges of the bearers.

8. A printing cylinder bearer having a cylindrical bore, a cylindrical peripheral face portion surrounding the bore in concentric spaced relation and defining the maximum thickness of the bearer, the length of the cylindrical peripheral face measured parallel to its aXis being less than diametrical dimensions of the bearer and which is greater in diameter at an intermediate portion than at its edges.

1,0. The combination with coacting rotary cylinders, of coacting bearers supported by the cylinders in rolling engagement, each bearer having an inner bore to engage its supporting cylinder, a crowned peripheral face surrounding the inner bore in concentric spaced relation and dening the thickness of the bearer, the edge portions of the crowned face curving inwardly toward the inner surface so that the thickness of the bearer is greater at "its intermediate portion than at its edges.

11. A printing cylinder bearer having a bore, a crowned peripheral face surrounding the bore in concentric spaced relation and defining the thickness of the bearer, the peripheral face curving inwardly toward the bore on a radius which is greater than the diameter of the bearer and whereby the thickness of the bearer is greater at an intermediate portion than at its edges.

WILLIAM F. HUCK. 

